Machine for making bifocal lenses.



Nof81'7,503,. PATENTED APR. l0, 1906. T. MUNDORPP.

MACHINE FOR MAKING BIFGAL LENSBS.

APPLIUATION FILED FBB.15, 1905.

2 SHEETS-SHEET 1.

Afro/2 No. 817,503. PATENTED APR. 1o, 1906.

' T. MUNDORP'P.

MACHINE PQR MAKING BIFOGAL LENSES.,

APPLIOATION FILED FEB.15, 1905.

z SHEETSLSHEBT z.

WTESSES.' 4 lli/VENTURI 4 (IML TheodwffMundwff lillblllllllill@ 1 AlllCE.

THEODURE MUNDORFF, OF NEW YORK, N. Y.

' llllMGl-lllhlll `lli-'Ull llllilllllGi BIHF'OCL LIENSESr i ne. erases.

Specification of Letters Patent.

Patented April 10, 1 906.

Application filed 'ebruary l5, 1905. Serial No. 245.662.

To all whom it may concern,.-

Be it known that l, Tnnonoan MUNDORFF, a citizen of the United States,residing in the city of New York, borough of Manhattan, in the county ofNew York and State or' N ew York, have invented certain new and 'usefullniproveinents in Machines for Making Bitocal Lenses, of which thefollowing is a speciiication. i

.My invention relates toa machine 'for niaking optical lenses of thatclass wherein a plurality of fields of diHerent radii are produced onthe surface of acne-piece lens. y [The object of this iinvention is theprovision of means by which a field of one radius `niay be produced onthe surface of a lens and at the saine time a ledge or shoulder, inter-I vening 'fields oi diii'erent radii, may be eliminated entirely fromthe lens.

A `further object is to conceal or cover on the lens a iield of oneradius while grinding a iield ci a diilerent radius on the exposed faceoli' the lens, thus obviatin g any contact oi the abrasive member with aground part of the lens durnlg the subsec nent treatment thereof.Reference is to be had to the accompany ing drawings, forming a part ofthis speciiication, wherein like characters ol' reference are used toindicate corresponding parts in all` the figures.

Figure 1 is a side elevation ol one form of machine for grinding opticallenses and eonstructed in accordance with my invention. Fig. 2 is anelevation taken at right'anglcs to liig. 1. Fig. 3 is a plan view of a.rotating head or work-holder, illustrating an incomplete lens inposition. to have one iield thereof stopped out and the remainingsurface of the lens ground to a dii'l'erent lield. Fig. 4 is a sectionalplan view taken in the plane of the dotted line 4 4 oi Fig 2, showingthe grinding or abrasiveinernberin position for operation on an exposed.face ol' the lens. Fig a perspective view of a preferred l'orm oigrindine or abrasive member. Fig. 6 is a vertica longitudinal sectionthrough the member shown by Fig. 5, and l `ig.l7 is a vverticaltransverse section through themeinber illustrated by Figs. 5 and l A Asdisclosed ina companion application iiled of even date herewith, Serial'N o. 245,663, I have produced a new` article.y in the shape of abilocal lens ,which is devoid oi" a ledge 'or shoulder intervening high`and'low power fields, said application,alsddisclosing.a new method ofproducing lensesoi this character. .My present application is for amachine adapted'to practice the process disclosed in the copendingapplication and to produce the new article claimed therein.

ln the drawings a Work-holder or head 5 is carried by a vertical shaft6, the latter being journaledv in a suitable bearing 7 and driven by anysuitable connections with a source of power, such as .a motor or aline-shaft- As shown, the holder or head 5 is in the forni of a disk adated to rotate in a horizontal plane, and on tlie upper `laoe of thisdisk is adapted to be secured the piece of glass which forms a blank7 oran embryo lens, the saine being indicated at A. It isevident that thislens in any suitable or preferred way but in prac-` tice said lens issecured to the holder by an adhesive, such Wax.

Before the blank or lens A is subjected to treatment in my machine aspace is reserved on the blank for a high-power 'field oll any d c siredradius to be produced thereon, as indi lated at o in Fig. 3. This fieldo is preferably ground on one surface of the lens in the usual or anypreferred manner, either before or alter grinding the lens in .inymachine said iield being of circular, elliptical, .,r any other shapeand preferably arranged within the edges of the blank or lens A. In thisoperation olz grinding the l'ield c on the lens, as ordinarily.practiced, a ledge or shoulder is produced on the surface of the lens,which ledge or shoulder defines or marks the outlines of the iield e. Toentirely overcome the production of this ledge or shoulder and at thesaine time produce a iield of low ower and of a different radius on thelens, have devised the machine shown by the drawings, the importantelement ol' which machine is the grinding tool or mel uber. (Shown byFigs. 4 to 7, inclusive.) l

vAnother important feature oi" m'y machine is a means for stopping outthe iield e of the embryo lens, and one embodiment of such suchstopping-out means is a disk plate or its equivalent. (Shown moreclearly by Figs. 1 and 4;) Asupport 8 of any suitable character is fixedquite close to the bearing 7 for the rotating shaft 6. This supportis'pr'ovided with a guide 9,`adapted 'to overhang the rotating holder 5and in this guide is mounted va spindle 10, the latter being adapted forIIO vertical adjustment.

ready threaded socketor openin duced thereon during The spindle isslidable freely in the guidefQ, and it is adapted to-be held in a iiXedposition by a binding-screw 11 the latter having a threaded bearin inthe guide: 9 and being adjustable by hanil so as to impinge the spindle10 and clamp it in place. The spindle is shown as having` a collar 12,against whichacts a coiled spring 1 3, which spring envelops the upperpart of said spindle, whereby the spring has a tendency to lift thespindle 'to a raised position away from the work on the rotating holder.The stopping-out member 14 is secured detachably to the lower part ofthe spindle 10. This member is adapted to cover the field a on the lensduring the period that the grinding or. abrasive member is operating onthe exposed surface ofthe lens.' Said stoppingout member 14 ma be ofanydesired size, shape, and materia and in practice I prefer to usedifierent shapes and sizes of said members. For this purpose the spindlel() andthe members are constructed to permit of the interchange of themembers 14. As shown by Fig. 1, the spindle 10 has a threaded ,stud 15,and each 'member' 14 has a whereby each member 14 may be vscrewe on thestud of the spindle. Itis evident that the stoppingout member may beeasily detached and replaced by another member, because the lower end ofthe spindle is always accessible. Furthermore, lthe member when attachedto thepindle is adjustable up and down therewit The distinctly novelfeature ofmy resent invention is the grindin -tool or mem er 16. Thismember,` is provided with aworking face. 17 of the desired radius. .Asshown, theworking face 17 is concave androvided onthe underside of thebody of said) tool or member 16. lenses are to be ground to a differentradii, I find it necessary to employ a' number of these grinding toolsor members., the workmg faces of which vary according to theradii of thelenses to bel produced. 'In practicethe` -thereon 1n any suitable forquently produced but .in some instances this appropriate way -tool mayhave the operation of. casting the tool, it being'i'mmaterial how thetool is; roduced. The tool is furthermore provi edwlth a slot 18, 'whichopens through the working face 17 thereof,- and for conveniencein'handling the .tool I'provide suitable lugs 19 on the back ofthe body.

The operation maybe described as follows: The embryo lens sired radiuson thelower part of said lens, ora space may be-reserv'ed on thelen's onwhich the high-power field is to loe-produced after the lensshall havebeen ground inthe present the desired working face pro-A Amay be firstprepared by 'producing the high-power field al of the de-f machine. Theoperator proceeds to secure the lens on the upper face of the rotativeber 1-4 is adjusted so that it'will not have actual contact with thereserved space or the field a, and the spindle 10 is held fixedly inplace by the clamping-screwv l1. Before the stoppin -out member islowe'red,1tl'1ev rindi-ng-too or abrasive member 16 shou d b`e placedover the lens so that the spindle 10 will pass through the slot 18. Theparts having ation, the shaft 6 is rotated at the required speed, soasto make the lens A turn in a horizontal plane. The working face 1"? oithe tool or member 16 is supplied with a suitable abrasive well known tothose skilled in the art, and'this tool is held or manipulatedby thevoperatorwhile the lens rotates; with the holder or head. T he operatormoves the tool back and forth across the exposed surface of" the lens,said tool having a transversin movement in a plane parallel to the planeo rotation of the lens with the holder 5. It will be seen that the toolis manipulated by th o erator to perform two classes of work on t e lenswhich is carried b holder: first, a lower-power ie sired radius isground on the exposed face of the lens, and, second, the lens is soroiind or treated a's to wholly overcome the ormation of theled Ve orshoulder between 'the highbeen adjusted into positions for opertherotating ns' of the de- Apower fiel c and the low-powerv field, whichoperation of thegrind-ing tool or member, f

because the stopping-out member 14 protects such reserved spaceor fieldc fromthe actionof the Ytool. When the grinding operation 'shall 4have'released and. the s prin'g 13 lifts thespindle and the meinber (1 4 toa position clear of the lens,V

tothe. ground on the exposed face of'saidl the* 'gh-power field a ofthelens und'er`treatbeen completed, the screwll is thus permitting thetool-16 to be .removed -and enable access to behad tothe lens A forremoving itV from the holder. Ofcourse the lens is subsequently,'treated, polished',- and finished in the described or any usual way.From. the foregoing descri tion it is to be understood that Vthe t'wofie ds may be. ro-

duced o n thelens in either of -two ways i rst,

by stopping out the 4space reserved'for the sir/,50s

face ground as set forth. In either case the des ed lields are producedWithout the objectionable ledge or shoulder.

Changes in the form, size, proportion, and minor details in constructionmay be made Without departing from the spirit of the invcntion orsacrificing any of the advantages thereof, and l. therefore reserve theright to maire suoli alterations and modifications as fairly fall Withinthe scope of my invention.

Having thus described my invention, what l claim new', and desire tosecure by Letters Patent, is" f l. The combination of a Work holder,means for stopping out a portion of a lens adapted to be fixed to saidholder, and a grinding member movable across the surface of a lens onsaid holder.

rlhe combination of a rotary Workholder, means for attaching a lens infixed position on said holder, and a grinding mem ber movable across asurface of a lens on said holder, said grinding member beingreciprocable in a plane substantially parallel to the plane oliotationof the work-holder.

3. The combination of a rcvoluble Workholder, adapted to give rotarymotion in a fixed plane to work carried thereon and an abrasive memberadapted to rest on said holder and reciprocable at Will across thesurface of a lens on said holder.

4. 'llio combination of a Work-holder and a grinding member, one of saidparts being revolnble in a 'lixed plane for giving rotary motion to alens fixed thereto and the other being movable relatively to the firstpart in a plane substantially parallel to the plane of rotation.

5. 'lhe combination of revoluble workliolder, means for ailixing thelens to`said holder and a grinding member movable rela tively to thework-holder and in a plane parallel to thc plane of rotation of saidWorin holder.

b. llie combination of a revoluble Work holder', means for stopping outaportiofi of a lens on said holder, and an abrasive member movablerelatively to the work-holder and the stoppingbut means.

'7. The combination of a revcluble Workw holder, means for stopping outa portion of a lens on said holder, and an abrasive member movablerelatively to the Worleholder a-nd l the stopping-out means, saidabrasive inem a grinding member, one rotating in a fixed plane and theother having movement relative to the first member, and means forstopping out a portion of the Work on said holder.

9. The combination of a movable Workholder, a stopping-out device, neansfor presenting said device to Work in said holder, and means fortreating the'worlr on said holder.

10. The combination of a revoluble workholder, a sto pping-out device,means for hold` ing said stopping-out device opposite to Work on saidholder, and means for treating the exposed surfacc of Work on saidholder.

11. The combination of a revoluble Workfor maintaining the stopping-outdevice in astationary position opposite to` the work-- holder.

12. The combination of a revoluble Workholder, a stopping-out device,and adjustable nected detachably to said presenting means.

14. The combination of a Work-holder, a support movable inapredetermined path relative to said vWork-holder, a stopping-out deviceon the support, and an abrasive meinber movable relative to the holderand spindle.

15. The combination of a Work-holder, a support movable toward theholder, a stopping-out device on the support, and an abrasive inember.

16. The combination of a Work-holder, a support movable toward theholder, a stopping-out device carried detachably by the support andadapted for use interchangeably with dilferent stopping-out devices, andan abrasive member.

17. In a machine for grinding lenses, an abrasive member adapted to bemoved relative to a lens and having a Working surface of a redeterminedradius extending longitudinrly and transversely thereof;

18. In a machine for grinding lenses, an abrasive member having aWorking surface of a given radius and controllable at will relative tothe lens upon the surface of which the member is adapted to operate.

19. vIn a machine for grinding lenses, the combination With aWork-holder, of an abrasive member having a Working surface of a givenrad-ius'and movable relative to said Work-holder- 20. In a machine forgrinding lenses, the

combination with a. work-holder,.of an abra sive member having a workingsurface of a given radius and movable relative to said 8o holder, astopping-out device, and a support IOO IIO

4: y A 817,503 Y '21., In a, machine for grinding lenses, the slottedgrinding rneinber, and a stopping-out combination with a Work-holder, ofa stopsupport fitted t0 the slot in said nieniber. pin-outdeviceforaiens,andagrinding mern- In testimony whereof I have signedmy ber, the Working surface ofewhieh has an openname torthisspecification in the presence of 5 ing to ceommodlrate tie stoRpiig-oultdeviee, two subscribing Witnesses.

'22. 'n a mae ine or grin ing enses, a l l A grinding member providedwith a Vertical THEODORE MUNDORFF' slot anden its bottom side with aWorking Witnesses:

surfaeeof-a desired radius, H. I. BERNHARD,

1Q 23s The combination of a Work-holder, a JAS. H. GRIFFIN.

